As well known, a human tissue image diagnostic apparatus (e.g., a breast cancer diagnostic apparatus) using microwaves is an apparatus for obtaining an image by radiating microwaves to the object whose image will be obtained. The apparatus is a medical apparatus in which when microwaves output from an output device pass through the object whose image will be obtained (e.g., a breast in the case of a breast cancer image diagnostic apparatus), an input device obtains information on the size and phase of a scattering signal (i.e., scattering microwaves), restores an image through an inverse scattering analysis based on the obtained information, and diagnoses whether or not cancer is present and the size and location of cancer from the restored image.
FIG. 1 shows the structure of a conventional breast cancer image diagnostic apparatus using a plurality of transmission and reception sensors (Meaney et al., Systems and Methods for 3-D Data Acquisition for Microwave Imaging, U.S. patent application Ser. No. 10/407,886, Apr. 4, 2003).
Referring to FIG. 1, in a conventional breast cancer image diagnostic apparatus, a plurality of transmission and reception sensors 100 #1-#N that are circularly arranged is fixed and disposed, and the breast 101 of an examinee is inserted between the sensors.
Thereafter, one (e.g., #1) of the plurality of sensors sends microwaves 102, receives microwave signals 103 scattered from the remaining sensors, and obtains information on the sizes and phases of the received microwave signals. Thereafter, the sensor #2 at another location sends microwaves, and the remaining sensors receive scattered microwave signals. This process is repeatedly performed up to the last sensor #N.
The conventional breast cancer image diagnostic apparatus restores a breast tomographic image of the examinee through a microwave inverse scattering analysis based on information on the size and phase of microwaves obtained from the sensors. In particular, when tumor tissue 104 having electrical characteristics (e.g., a dielectric constant and conductivity) different from those of breast tissue is present in the breast of the examinee, information on a received microwave signal is different from that when tumor tissue is not present, and whether or not a tumor is present within the breast is diagnosed based on the information.
As described above, in the prior art, an image is restored by fixing and disposing a plurality of transmission and reception sensors at constant intervals around the breast. Furthermore, in order to restore a three-dimensional (3-D) image, a task for vertically moving the sensors also needs to be performed.